Development of a loop-mediated isothermal amplification (LAMP) assay based on the C962R gene for african swine fever virus detection
Abstract
Aim. The aim of this study was to develop a loop-mediated isothermal amplification (LAMP) assay for African swine fever virus (ASFV) detection. Methods. Primer design was performed using publicly available full genome sequences of ASFV. A panel of heterologous DNA samples and reference ASFV DNA samples were used for the assay specificity testing. The limit of detection (LOD) was assessed using purified and quantified serial dilution of the amplified target sequence. LAMP product detection was performed via gel-electrophoresis and via ethidium bromide fluorescence under UV after adding the ethidium bromide directly to the tube with the LAMP product. Results. Three primer sets amplifying different regions of ASFV gene C962R were developed, of which the set № 2 providing the most intense product synthesis with the most vivid and clear pattern was selected for further studies. The optimal concentration of reaction mix components for the most effective primer set was established. In the final protocol the LAMP reaction was carried out at 60 °C for 40 min. The limit of detection (LOD) of the assay was 50 copies of the target sequence per reaction. In a preliminary testing the assay proved specific, using 10 reference and 4 heterologous viral and two bacterial DNA samples. Our LAMP assay detected ASFV genotypes I and II that are currently spread in Europe, Asia, and the Pacific and IX, occurring in Africa. Conclusion. A LAMP assay was developed based on the C962R gene that proved in preliminary validation to be specific and sensitive and was able to detect down to 50 copies per reaction of purified target gene within 40 minutes. Classical gel electrophoresis and direct staining using ethidium bromide were used for product visualisation in this study. Colorimetric approaches or the use of lateral flow devices in the visuali- sation step could make the assay less equipment dependent. Further validation of the assay, determining analytical specificity, selectivity and reproducibility performance characteristics also using clinical samples under field condi- tions and inclusion of an internal control would possibly enable its use as a test of choice at point-of-care and at low resource laboratories.References
Alonso C, Borca M, Dixon L et al. (2018) ICTV Virus Taxonomy Profile: Asfarviridae. J. General Virology. 99:613–614. doi: 10.1099/jgv.0.001049
APHA (Animal and Plant Health Agency) (2022) Updated Outbreak Assessment #24. African swine fever in Europe. Available at: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1047016/ASF_in_Eastern_Europe_24.pdf. Accessed 27 Jan 2022
Baek YH, Um J, Antigua KJ et al. (2020) Development of a reverse transcription-loop-mediated isothermal amplification as a rapid early-detection method for novel SARSCOV-2. Emerging Microbes & Infections. 9:998–1007. doi: 10.1080/22221751.2020.1756698
Bao J, Wang Q Lin P et al. (2018) Genome comparison of African swine fever virus China/2018/ AnhuiXCGQ strain and related European p72 Genotype II strains. Transboundary and Emerging Diseases. 66:1167–1176. doi: 10.1111/tbed.13124
Blome S, Franzke K, Beer M. (2020) African swine fever – a review of current knowledge. Virus Res. 287:198099. doi: 10.1016/j.virusres.2020.198099
Balasuriya UBR, Barratt-Boyes S, Beer M et al. (2017) Asfarviridae and Iridoviridae. In MacLachlan NJ, Dubovi EJ (ed) Fenner’s Veterinary Virology (5th edn). Academic Press. 175–188 p. doi.org/10.1016/B978-0-12-800946-8.00008-8
Beltrán-Alcrudo D, Lubroth J, de La Rocque S, Depner K. (2008) African swine fever in the Caucasus. EMPRES watch:1–8. doi: 10.13140/RG.2.1.3579.1200
Beltrán-Alcrudo D, Arias M, Gallardo C et al. (2017) African swine fever: detection and diagnosis – A manual for veterinarians. FAO Animal Production and Health Manual No. 19. Rome. Food and Agriculture Organization of the United Nations (FAO). 88 p
Chapman DAG, Tcherepanov V, Upton Ch et al. (2008) Comparison of the genome sequences of non-pathogenic and pathogenic African swine fever virus isolates. J. General Virology. 89:397–408. doi: 10.1099/vir.0.83343-0
Chapman DAG, Darby AC, Da Silva M et al. (2011) Genomic analysis of highly virulent isolate of African swine fever virus. Emerging Infectious Diseases. 17(4):599–605. doi: 10.3201/eid1704.101283
Cwynar P, Stojkov J, Wlazlak K. (2019) African swine fever status in Europe. Viruses. 11:310. doi: 10.3390/v11040310
Desmecht D, Gerbier G, Gortázar Schmidt C et al. (2021) Epidemiological analysis of African swine fever in the European Union (September 2019 to August 2020). EFSA Journal. doi: 10.2903/j.efsa.2021.6572
Dixon LK, Chapman DAG, Netherton ChL, Upton Ch. (2012) African swine fever virus replication and genomics. Virus Res. 173:3–14. doi: 10.1016/j.virusres.2012.10.020
Dixon LK, Sun H, Roberts H. (2019) African swine fever. Antiviral Res. 165:34–41. doi: 10.1016/j.antiviral.2019.02.018
Dokphut A, Boonpornprasert P, Songkasupa T, Tangdee S. (2020). Development of a loop-mediated isothermal amplification assay for rapid detection of African swine fever. Veterinary Integrative Sci. 19:87–100.
Elsukova AA, Vlasova NN, Igolkin AS. (2019) Sinteticheskie oligonukleotidnye praimery i sposob vyyavleniya dnk virusa achs metodom petlevoy izotermicheskoy amplifikacii. Federalnoe gosudarstvennoe byudzhetnoe uchrezhdenie «Federalnyy centr ohrany zdorovya zhivotnyh» (FGBU «VNIIZZh»). Patent No. 0002710065. https://edrid.ru/rid/219.017.f243.html (in Russian).
FAO (The Food and Agriculture Organization) (2022) ASF situation in Asia & Pacific update. Available at: https://www.fao.org/ag/againfo/programmes/en/empres/ASF/situation_update.html. Accessed 27 Jan 2022
Fernández-Pinero J, Gallardo C, Elizalde M et al. (2012) Molecular diagnosis of African swine fever by a new real-time PCR using Universal Probe Library. Transboundary and Emerging Diseases. 60:48–58. doi: 10.1111/j.1865-1682.2012.01317.x
Francois P, Tangomo M, Hibbs J et al. (2011) Robustness of a loop-mediated isothermal amplification reaction for diagnostic applications. FEMS Immunol. Med. Microbiol. 62:41–48. doi: 10.1111/j.1574-695x.2011.00785.x
Gaudreault NN, Madden DW, Wilson WC et al. (2020) African swine fever virus: An emerging DNA arbovirus. Frontiers in Veterinary Sci. doi: 10.3389/fvets.2020.00215
GenBank overview (no date) Nih.gov. Available at: https://www.ncbi.nlm.nih.gov/genbank/ (Accessed: January 31, 2022).
Goto M, Honda E, Ogura A et al. (2009) Colorimetric detection of loop-mediated isothermal amplification reaction by using hydroxy naphthol blue. BioTechniques. 46:167–172. doi: 10.2144/000113072
James HE, Ebert K, McGonigle R et al. (2010) Detection of African swine fever virus by loop-mediated isothermal amplification. J. Virolog. Methods. 164:68–74. doi: 10.1016/j.jviromet.2009.11.034
Kashir J, Yaqinuddin A. (2020) Loop mediated isothermal amplification (LAMP) assays as a rapid diagnostic for COVID-19. Med. Hypotheses. 141:109786. doi: 10.1016/j.mehy.2020.109786
King DP, Reid SM, Hutchings GH et al. (2003) Development of a taqman® PCR assay with internal amplification control for the detection of African Swine Fever virus. J. Virolog. Methods. 107:53–61. doi: 10.1016/s0166-0934(02)00189-1
Lamarche BJ, Kumar S, Tsai M-D. (2006) ASFV DNA Polymerase X is Extremely Error-Prone Under Diverse Assay Conditions and Within Multiple DNA Sequence Contexts. Biochemistry. 45:14826–14833. doi: 10.1021/bi0613325
LAMP Primer Designing Software. In: PrimerExplorer. http://primerexplorer.jp/lampv5e/index.html. Accessed 12 Oct 2021
Lvov DK, Shchelkanov MY, Alkhovsky SV, Deryabin PG. (2015) Double-stranded DNA viruses. In Zoonotic Viruses in Northern Eurasia. Academic Press. 393–406 p. doi: 10.1016/b978-0-12-801742-5.00009-x
Mansour SM, Ali H, Chase CC, Cepica A. (2015) Loop-mediated isothermal amplification for diagnosis of 18 World Organization for Animal Health (OIE) notifiable viral diseases of ruminants, swine, and poultry. Anim.Health Res. Rev. 16:89–106. doi: 10.1017/s1466252315000018
Mee PT, Wong S, O’Riley KJ et al. (2020) Field verification of an African swine fever virus loop-mediated isothermal amplification (LAMP) assay during an outbreak in Timor-Leste. Viruses 12:1444. doi: 10.3390/v12121444
Nagamine K, Hase T, Notomi T. (2002) Accelerated reaction by loop-mediated isothermal amplification using loop primers. Mol. Cell. Probes. 16:223–229. doi: 10.1006/mcpr.2002.0415
Notomi T. (2000) Loop-mediated isothermal amplification of DNA. Nucl. Acids Res. doi: 10.1093/nar/28.12.e63
OIE (World Organisation for Animal Health) (2019a) Global situation of ASF. Report No. 17 (2016-2019). Available at: https://www.oie.int/fileadmin/Home/eng/Animal_Health_in_the_World/docs/pdf/Disease_cards/ASF/Report_17._Global_situation_of_ASF.pdf. Accessed 13 Oct 2021
OIE (World Organisation for Animal Health) (2019b) Manual of Diagnostic Tests and Vaccines for Terrestrial Animals. Available at: https://www.oie.int/fileadmin/Home/eng/Health_standards/tahm/3.08.01_ASF.pdf. Accessed 13 Oct 2021
OIE-WAHIS (the World Animal Health Information System of the World Organisation for Animal Health) (2021) African Swine Fever (ASF) – Situation report 3. Available at: https://www.oie.int/app/uploads/2022/01/asf-situation-report-3.pdf. Accessed 27 Jan 2022
Park G-S, Ku K, Baek S-H et al. (2020) Development of reverse transcription loop-mediated isothermal amplification assays targeting severe acute respiratory syndrome coronavirus 2 (SARS-COV-2). J. Mol. Diagnos. 22:729–735. doi: 10.1016/j.jmoldx.2020.03.006
Phillips DE, Mee PT, Lynch SE et al. (2021) Use of field-based loop-mediated isothermal amplification (LAMP) technology for a prevalence survey and proof of Freedom Survey for African swine fever in Timor-Leste in 2019. Frontiers in Veterinary Sci. doi: 10.3389/fvets.2021.672048
Ramirez-Medina E, Vuono EA, Rai A et al. (2020) The C962R ORF of African Swine Fever Strain Georgia is Non-Essential and not Required for Virulence in Swine. Viruses. 12(6):676. doi: 10.3390/v12060676
Tran DH, Tran HT, Le UP et al. (2020) Direct colorimetric lamp assay for rapid detection of African Swine Fever Virus: A validation study during an outbreak in Vietnam. Transboundary and Emerging Diseases. doi: 10.1111/tbed.13879
Vuono EA, Ramirez-Medina E, Pruitt S et al. (2021) Evaluation of the Function of the ASFV KP177R Gene, Encoding for Structural Protein p22, in the Process of Virus Replication and in Swine Virulence. Viruses. 13(6):986. doi: 10.3390/v13060986
Wang D, Yu J, Wang Y et al. (2020) Development of a real-time loop-mediated isothermal amplification (LAMP) assay and visual lamp assay for detection of African Swine Fever Virus (ASFV). J. Virological Methods. 276:113775. doi: 10.1016/j.jviromet.2019.113775
Wang G, Xie M, Wu W et al. (2021) Structures and Functional Diversities of ASFV Proteins. Viruses 13:2124. doi: 10.3390/v13112124
Wong Y-P, Othman S, Lau Y-L et al. (2018) Loop-mediated isothermal amplification (LAMP): A versatile technique for detection of microorganisms. J. Appl. Microbiol. 124:626–643. doi: 10.1111/jam.13647
Wu X, Xiao L, Wang Y et al. (2016) Development of a rapid and sensitive method for detection of African swine fever virus using loop-mediated isothermal amplification. Brazilian Archives of Biology and Technology. doi: 10.1590/1678-4324-2016160500
Zani L, Forth JH, Forth L et al. (2018) Deletion at the 5′- end of Estonian ASFV strains associated with an attenuated phenotype. Scientific Reports. 8:6510. doi: 10.1038/s41598-018-24740-1
Zhu Zh, Xiao Ch-T, Fan Y et al. (2019) Homologous recombination shapes the genetic diversity of African swine fever viruses. Veterin. Microbiol. 236:108380. doi: 10.1016/j.vetmic.2019.08.003

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.


